Date: Mon, 06 Apr 2026 17:00:25 +0000 From: Ed Maste <emaste@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 7764e9ca28a9 - main - fmax.3: Add caveat for going beyond C std requirements Message-ID: <69d3e6a9.1cf0c.4efc1da3@gitrepo.freebsd.org>
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The branch main has been updated by emaste: URL: https://cgit.FreeBSD.org/src/commit/?id=7764e9ca28a9702aed4ba7391e055ec2fcf35c41 commit 7764e9ca28a9702aed4ba7391e055ec2fcf35c41 Author: Ed Maste <emaste@FreeBSD.org> AuthorDate: 2026-04-02 21:59:42 +0000 Commit: Ed Maste <emaste@FreeBSD.org> CommitDate: 2026-04-06 17:00:15 +0000 fmax.3: Add caveat for going beyond C std requirements libm's fmax and fmin family of functions treat +0.0 as greater than -0.0. This is not required by the C standard, so the user may not see this behaviour due to compiler optimization. PR: 294214 Reviewed by: fuz Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D56230 --- lib/msun/man/fmax.3 | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/lib/msun/man/fmax.3 b/lib/msun/man/fmax.3 index 25fc9b6d518a..873a19375ce5 100644 --- a/lib/msun/man/fmax.3 +++ b/lib/msun/man/fmax.3 @@ -22,7 +22,7 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.Dd June 29, 2004 +.Dd April 6, 2026 .Dt FMAX 3 .Os .Sh NAME @@ -68,10 +68,6 @@ functions return the smaller of .Fa x and .Fa y . -They treat -.Li +0.0 -as being larger than -.Li -0.0 . If one argument is an \*(Na, then the other argument is returned. If both arguments are \*(Nas, then the result is an \*(Na. These routines do not raise any floating-point exceptions. @@ -90,6 +86,13 @@ and .Fn fminl functions conform to .St -isoC-99 . +.Sh CAVEATS +The library implementations of these functions treat +.Li +0.0 +as being larger than +.Li -0.0 . +This behavior is not specified by the C standard, is not portable, +and may not occur in light of compiler optimizations. .Sh HISTORY These routines first appeared in .Fx 5.3 .home | help
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